RAM and compatibility

I want to get 512MB more RAM, with two 256MB sticks. On the memoryx.net site, they had a tool that would check which motherboard you have, and what ram you can buy from them that would be compatible with your board.

Not worth it at all. $250 for 512MB of RAM. Seriously, I don't care how slow your computer is, just save that money towards something new. Spend 2x-3x that amount and you are going to see a speed increase you won't believe.

Just an FYI about RAM, some mobos default to different voltages, this can create problems.

In my case I have a Striker Extreme 680i, which defaults memory to 1.8v 1T. Now the Corsair Dominator RAM I use requires 2.1v to run. So in order to make it work (ie even POST to get into BIOS) I had to use a cheapo stick of 1.8v memory to get in, set VDIMM manually, plug in the memory, set all timings and values, and then go.

Now this sort of bullshit behavior really only happens on high value boards, but I've seen it enough to mention it.

As for compatibility according to this ebay guide you need to match the FSB to the ram speed so in your case you'll need PC1066

Umm, no, very wrong. FSB isn't really linked to memory speed anymore, and you'll need to double that memory speed to convert it to the FSB anyways. AKA ddr2 6400 PC800 would be a 1600 FSB, you have more then enough room. RAM speeds over that are for overclocking, and you can even do that with 6400 RAM. Toss in the fact that the system will work faster when all speeds are linked and memory 6400 and up pretty much demands you overclock to see the real gains from it, that or unlink it for some gain.

Not automatically

In this case it needs to be have an FSB of 800 or more which the Pentium 4 640 does. Still that's a pretty old, and fairly rubbish CPU, you'd be much better of buying a shiney new one.

Depends on BIOS updates. Just because a board supports something doesn't mean it ships with a BIOS that will.

waterlogged on January 2008

Democrat that will switch parties and turn red if Clinton is nominated.:P[SIGPIC][/SIGPIC]

As for compatibility according to this ebay guide you need to match the FSB to the ram speed so in your case you'll need PC1066

Umm, no, very wrong. FSB isn't really linked to memory speed anymore, and you'll need to double that memory speed to convert it to the FSB anyways. AKA ddr2 6400 PC800 would be a 1600 FSB, you have more then enough room. RAM speeds over that are for overclocking, and you can even do that with 6400 RAM. Toss in the fact that the system will work faster when all speeds are linked and memory 6400 and up pretty much demands you overclock to see the real gains from it, that or unlink it for some gain.

I know it's true now, especially with DDR, but RDRAM I'm not so sure, especially mixing modules from different manufacturers. It's fussy, it needs to be installed in matched pairs etc. I wouldn't bother with the risk considering the price.

Not automatically

In this case it needs to be have an FSB of 800 or more which the Pentium 4 640 does. Still that's a pretty old, and fairly rubbish CPU, you'd be much better of buying a shiney new one.

Depends on BIOS updates. Just because a board supports something doesn't mean it ships with a BIOS that will.

As for compatibility according to this ebay guide you need to match the FSB to the ram speed so in your case you'll need PC1066

Umm, no, very wrong. FSB isn't really linked to memory speed anymore, and you'll need to double that memory speed to convert it to the FSB anyways. AKA ddr2 6400 PC800 would be a 1600 FSB, you have more then enough room. RAM speeds over that are for overclocking, and you can even do that with 6400 RAM. Toss in the fact that the system will work faster when all speeds are linked and memory 6400 and up pretty much demands you overclock to see the real gains from it, that or unlink it for some gain.

I know it's true now, especially with DDR, but RDRAM I'm not so sure, especially mixing modules from different manufacturers. It's fussy, it needs to be installed in matched pairs etc. I wouldn't bother with the risk considering the price.

Not automatically

In this case it needs to be have an FSB of 800 or more which the Pentium 4 640 does. Still that's a pretty old, and fairly rubbish CPU, you'd be much better of buying a shiney new one.

Depends on BIOS updates. Just because a board supports something doesn't mean it ships with a BIOS that will.

"in this case" means I've bothered looking up the answer.

Again, boards support MANY fsb ratings depending on bios. So the same board will/won't work with the same CPU depending on the BIOS shipped, and the site, adverts, change with that, but do not always equate to the BIOS you get shipped.

waterlogged on January 2008

Democrat that will switch parties and turn red if Clinton is nominated.:P[SIGPIC][/SIGPIC]

So could I still use a 800 sticks with the 1066 I have inside already? I have updated my BIOS for the board to the latest version. I was planning on two 256 sticks since I think my board has to have the RAM installed in pairs.

Why I'm asking about the 800 is that its only $69 bucks or so for one stick, so $130 for both is decent for me. I really don't want to spend more to get a new board, cpu, ram etc, since I think upgrading to 1 gig will be more than enough for me for a long while yet (to be honest, I'm doing this mostly for WoW, as I've heard that upgrading to 1 gig makes a world of difference in speed etc).

So could I still use a 800 sticks with the 1066 I have inside already? I have updated my BIOS for the board to the latest version. I was planning on two 256 sticks since I think my board has to have the RAM installed in pairs.

Why I'm asking about the 800 is that its only $69 bucks or so for one stick, so $130 for both is decent for me. I really don't want to spend more to get a new board, cpu, ram etc, since I think upgrading to 1 gig will be more than enough for me for a long while yet (to be honest, I'm doing this mostly for WoW, as I've heard that upgrading to 1 gig makes a world of difference in speed etc).

Honestly we'd have to see the rest of your specs to make a judgment; depending on your processor/graphics card it might make a difference, but it doesn't seem worth it for $130 when you could have the start of a better machine for like $300...